At a surfboard-makers supply store, I bought a $228 SUP blank—a 10-foot 4-inch rectangular slab of expanded polystyrene (EPS) foam with a strip of basswood known as the stringer running through the center. You can also purchase one of these online. Be aware: EPS requires epoxy resin, because polyurethane resin will melt it. (This is important!)

I trucked that blank home and stared at it. It already had a rocker, which is a gradual curve from nose to tail, like the upturn in a boat's prow. A rocker keeps the nose from burying itself in the water while you're riding and also lifts the front of the board under wave power. I could adjust for more or less rocker as I shaped. But first I had to do the rough cut, which you can do with just about any kind of handsaw and a template, much like cutting cloth with a pattern. For my template, I traced a borrowed 10-foot SUP on 30-pound roofing felt with a white pencil. I traced half a SUP lengthwise, I should say, with the machined edge of the felt to be lined up with the blank's stringer. By tracing a hemisphere and doubling it by flipping it, you are assured of symmetry.

With a very sharp 10-inch pull saw, I followed my outline, making a few cuts from the outside edge to the cut line to free up the saw in the curves—a scissoring trick learned in kindergarten. Mostly I was in awe of the saw and its silent, near effortless progress through the buttery--smooth EPS foam.

I could've taken that rough cut, rounded the edges, and had a perfectly functional SUP shape for flat water. It would've surfed too. But I was more ambitious than that. I wanted to take about an inch off the deck—the top part where you stand—doming it gracefully down to perfectly rounded rails (the sides) for smooth turning. I wanted high functionality: speed, control, and maneuverability. I wanted to shape.

Hand-shape, I should specify, unaided by expensive power tools. I picked up the saw again, marking it with tape at ¾ inch, and made numerous vertical cuts in the deck to that depth. I had measured and marked the rails for desired thickness (4½ inches at the thickest point) and made sure to leave at least ½ inch of foam above the marks. Then I cut in horizontally from the rails to the stringer, lifting off slabs of foam I wouldn't have to shave off later. Essentially, I used the pull saw to do the job of a $400 power planer. I carved that baby like a standing rib roast, and when I was done I thought, oh my God, what have I done? It didn't look pretty. But I had not yet, I reassured myself, trespassed into the ideal board that still existed inside that angular debris field.

Somewhat dubiously, I moved on to the next tool—a 14-inch 50-grit drywall rasp. Within 15 minutes I was competent. After an hour I was in love. I was "mowing foam" (as shapers say) in long smooth strokes, albeit at a rate of maybe 1⁄128 inch at a time. I put on some rock 'n' roll and went into a shaper's trance, alternating at times between the rasp and a palm-sized hand plane for the wooden stringer. I did some measuring along the way, but not a lot. A surfboard is essentially a spear point for cutting through water, and I believe we all possess a deeply atavistic knowledge of honing such things.

Following up with a lighter sanding block with an 80-grit screen, I polished the foam to an admirable sheen, smooth as a baby's behind. And I stuck a handle on the side with epoxy.

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2Laminating

Nathaniel Welch

In the real world the shaper and the glasser aren't usually the same person. The shaper is the rock star, the thinker, the artiste. The glasser is the technician, the dude with the job you don't want. You can shape at leisure, but once you pour hardener into your resin the clock is ticking. You want to work quickly but not frantically. Good luck!

Before mixing my first pour of epoxy resin and hardener (in a 2:1 ratio), I watched a lot of instructional YouTube, so much so that I was undeniably procrastinating. In the end, your first glass job is a baptism by liquid fire. I survived. My SUP survived. But it was a close thing, at times a bit harrowing.

The weight (thickness) of the fiberglass and the number of layers to be applied are known in the trade as the glass schedule. My schedule called for one layer of 6-ounce fiberglass for the bottom and two layers of 6-ounce on the deck, where you need the most protection. Laminating is akin to tailoring: You lay out the glass on the board and cut so that it overhangs by about 3 inches and wraps around the underside in a snug fit. This requires darting to accommodate the curves.

You laminate the bottom of the board first, and if you're smart you'll masking--tape the entire deck to protect it from splashes. To laminate the deck, you cut one layer of fiberglass to fit (the easy cut) and then a second layer that goes on top of the first and overlaps by 3 inches (as with the bottom layer). Gently smooth them out by hand, from the center to the tail, and from the center to the nose, until there are no wrinkles. Then pour and spread epoxy over the two deck layers. Having done the bottom the day before, I was already more competent with the little plastic spreader tool. I spread the epoxy with long strokes, listening for a zinging sound that means the glass is fully saturated. Pull and bring the excess to the rails, and wrap the fiberglass underneath, catching drips in your mixing bucket, repouring excess epoxy where needed.

At lamination's end, to my relief, I found I was somehow well within the parameters of the acceptable. The good news is, if all goes mostly well, there's nothing you can't fix. Lumps can be sanded. Thin spots retouched with a small batch of resin. Ding repair, as I said. After the resin and fiberglass layers have dried completely, in 24 to 48 hours, both the bottom and the deck receive another epoxy layer, called the hot coat. This is also another opportunity to give the board a smooth, glossy finish. Finally, I installed the finishing touches: a leash cup to hold the leash, the fin box, and the fin on the bottom. I glued a deck pad to the deck over where I'd be standing.

My end result (see page 103) was surprisingly successful, admirably light, and nimble in the water. The SUP passed its flat-water test with flying colors, floating a 200-pound test pilot. The surf test awaits. But hurricane season is here, and when the next named storm rumbles up the Atlantic Coast, that SUP will ride the swells. I'm stoked.

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3A step-by-step guide to your new paddleboard

Brown Bird Design

Building a paddleboard is simple in theory, but can be complicated in practice. These are the general steps, but plan to do some research on the shape you like and the tools you want to use before you get started.

Trace half of a borrowed SUP or printed template onto roofing felt. You'll flip the felt when you transfer the shape onto the foam.

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4

Brown Bird Design

After drawing the shape on the foam, use a 10-inch pull saw to cut around the outline. You may need to cut in from the sides to free up the saw.

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5

Brown Bird Design

To remove bulk in advance of hand shaping, make 3/4-inch cuts into the foam from above, then saw them off horizontally, like a rib roast.

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6

Brown Bird Design

Hone the board into shape with a ­drywall rasp and a hand plane. It should look like a curved spear point, with no rough edges.

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7

Brown Bird Design

Cut out three pieces of fiberglass cloth—two for the top and one for the bottom. You may have to fold it at the corners to keep everything smooth.

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8

Brown Bird Design

Lay the fiberglass on the board, mix the epoxy, and pour the epoxy over the fiberglass. Spread the epoxy with the included tool.

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